Biopolymer-Based Food Packaging: Functional Properties, Enhancement Strategies, and Future Perspectives.

The increasing global demand for food and growing environmental concerns have intensified efforts to develop sustainable alternatives to conventional petroleum-based food packaging materials. Food packaging plays a critical role in preserving product quality, ensuring food safety, and extending shelf life across the supply chain. However, the extensive use of non-biodegradable plastics has contributed significantly to environmental pollution and resource depletion, encouraging the development of renewable and eco-friendly materials. Biopolymers have attracted considerable attention as greener alternatives due to their biodegradability, reduced carbon footprint, and the ability of optimized formulations to achieve oxygen barrier properties comparable to certain petrochemical plastics. This review summarizes the sources, classifications, and key functional properties of biopolymer-based packaging materials including barrier, mechanical, optical, and thermal characteristics. Recent advances in active packaging systems such as antimicrobial and antioxidant biopolymer-based materials are also discussed. Nevertheless, despite these advantages, major limitations, including high moisture sensitivity, weak mechanical performance, and limited scalability, still hinder their widespread industrial application. In addition, substantial research gaps remain regarding long-term performance and real-world environmental impact. Applications in different food sectors are examined alongside environmental and regulatory aspects. This review provides a critical evaluation of performance enhancement strategies, including polymer modification, nanocomposites, and bioactive incorporation, highlighting both their effectiveness and limitations. Compared with conventional plastics, biopolymers generally exhibit lower barrier and mechanical properties, yet recent studies indicate that nanocomposite approaches can improve barrier performance by up to 30%-50%. Overall, biopolymer-based packaging represents a promising approach for sustainable food systems. Future research should focus on bridging the gap between laboratory-scale innovation and industrial implementation, particularly in terms of cost-efficiency and large-scale production.